Mutations in the erythropoietin receptor gene are not a common cause of Diamond-Blackfan anemia

Diamond-Blackfan anemia (DBA) is an inherited pure red blood cell aplasia that often requires lifelong transfusional support. The origin of the imperfect erythrogenesis is not known. The existence of more than one molecular basis for DBA is indicated by its different modes of inheritance and widely variable clinical phenotypes. Several erythroid growth factors have been thought to have a role in the pathogenesis of DBA. However, there is neither molecular nor clinical evidence for the involvement of stem cell factor or interleukin-3. The observation of elevated erythropoietin (EPO) concentrations and an impaired in vivo and in vitro response to pharmacologic doses of recombinant human EPO has suggested a defective EPO function in the pathogenesis of DBA. We have investigated the possible involvement of the EPO receptor (EPO-R) gene in 23 patients by screening its coding sequence for mutations using single-strand conformation polymorphism (SSCP). A Southern blot and hybridization with an EPO-R probe was also performed on DNA from seven patients. No causal mutations were identified. The absence of concordant segregation of the disease with the EPO-R gene in two informative families ruled out its role in their OBA children. These findings demonstrate that DBA is not commonly associated with EPO-R gene mutations.